package com.gitee.melin.bee.core.grpc.protobuf;

import com.google.protobuf.ExtensionRegistry;
import com.google.protobuf.Message;
import com.google.protobuf.UnknownFieldSet;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.charset.Charset;

public abstract class ProtobufFormatter {
    private Charset defaultCharset = Charset.defaultCharset();

    /**
     * Set the default character set to use for input / output data streams
     *
     * @param cs the character set to use by default, when unspecified
     */
    public void setDefaultCharset(Charset cs) {
        defaultCharset = cs;
    }

    /**
     * Get the default character set to use for input / output streams
     *
     * @return the character set to use by default, when unspecified
     */
    public Charset getDefaultCharset() {
        return defaultCharset;
    }

    /**
     * @param message the protobuf message to format
     * @param output the stream to write the formatted message using the default charset
     * @throws IOException
     */
    public void print(final Message message, OutputStream output) throws IOException {
        print(message, output, defaultCharset);
    }

    /**
     * Outputs a textual representation of the Protocol Message supplied into the parameter output.
     * (This representation is the new version of the classic "ProtocolPrinter" output from the
     * original Protocol Buffer system)
     *
     * @param message the protobuf message to format
     * @param output the stream to write the formatted message
     * @param cs the character set to use
     * @throws IOException
     */
    public abstract void print(final Message message, OutputStream output, Charset cs) throws IOException;

    /**
     * @param fields unknown fields to format
     * @param output output the stream to write the formatted message using the default charset
     * @throws IOException
     */
    public void print(final UnknownFieldSet fields, OutputStream output) throws IOException {
        print(fields, output, defaultCharset);
    }

    /**
     * @param fields unknown fields to format
     * @param output output the stream to write the formatted message
     * @param cs the character set to use
     * @throws IOException
     */
    public abstract void print(final UnknownFieldSet fields, OutputStream output, Charset cs) throws IOException;

    /** Like {@code print()}, but writes directly to a {@code String} and returns it. */
    public String printToString(final Message message) {
        try {
            ByteArrayOutputStream out = new ByteArrayOutputStream();
            print(message, out, defaultCharset);
            out.flush();
            return out.toString();
        } catch (IOException e) {
            throw new RuntimeException("Writing to a StringBuilder threw an IOException (should never happen).", e);
        }
    }

    /** Like {@code print()}, but writes directly to a {@code String} and returns it. */
    public String printToString(final UnknownFieldSet fields) {
        try {
            ByteArrayOutputStream out = new ByteArrayOutputStream();
            print(fields, out, defaultCharset);
            out.flush();
            return out.toString();
        } catch (IOException e) {
            throw new RuntimeException("Writing to a StringBuilder threw an IOException (should never happen).", e);
        }
    }

    /** Thrown when parsing an invalid text format message. */
    public static class ParseException extends IOException {
        private static final long serialVersionUID = 1L;

        public ParseException(String message) {
            super(message);
        }
    }

    /**
     * Parse a text-format message from {@code input} and merge the contents into {@code builder}.
     */
    public abstract void merge(
            final InputStream input, Charset cs, ExtensionRegistry extensionRegistry, final Message.Builder builder)
            throws IOException;

    /**
     * Parse a text-format message from {@code input} and merge the contents into {@code builder}.
     */
    public void merge(final InputStream input, Charset cs, final Message.Builder builder) throws IOException {

        merge(input, cs, ExtensionRegistry.getEmptyRegistry(), builder);
    }

    public void merge(final InputStream input, final Message.Builder builder) throws IOException {

        merge(input, defaultCharset, ExtensionRegistry.getEmptyRegistry(), builder);
    }

    public void merge(final InputStream input, ExtensionRegistry extensionRegistry, final Message.Builder builder)
            throws IOException {
        merge(input, defaultCharset, extensionRegistry, builder);
    }
}
